It seems like when I click the blue text it should take me to that definition or open it as a pop-up or something. Not sure why it doesn’t. If this is a misconception on my part, please let me know.
Just in case it matters, I was using an Apple Pencil. But it also doesn’t do it if I use my finger. I noticed that if I look through other definitions, where there are blue head words, which appeared to be links, clicking them also does nothing.
These seem to be specifically broken links, rather than link functionality being broken for all dictionaries - will investigate why they're not working.